Prescription Lenses for glasses are designed to correct specific vision errors of the eye as prescribed by an eye doctor. Such errors include Hyperopia (farsightedness), Myopia (near sightedness), and Astigmatism, where light rays are broken up as they enter the eye and do focus properly on the retina and produce a single image. While many people enjoy perfect vision from infancy into their middle ages, most find that as they progress through their 40’s that they develop Presbyopia, in which they experience difficulty focusing for near vision and need prescription eyeglass lenses for comfortable reading. Rx Lenses work by refracting (or bending) light as it passes through the lens. Each Rx Lens is ground to match the prescription issued by your eye doctor at the completion of your eye examination. So your prescription eyeglass lenses are individualized and custom made just for you!